1. Field of the Invention
The invention relates to a device comprising a bolt which is to be inserted into a receiving hole, e.g. a screw bolt which is to be screwed into a threaded bore, and an axially displaceable coupling part which may be brought to engage at the end part of the bolt, may be driven so as to rotate, and by means of which a rotational movement and an axial force, in particular simultaneous at least at times, may be transmitted to the bolt.
2. Description of the Prior Art
Screw connections to flanges, covers, and closures of pressure containers, reactor vessels, and the like are in many instances, constructed in such a way that the front-end closing surface or a flange of a vessel has threaded bores which are disposed on a bolt hole circle and into which screw bolts formed as stud bolts are screwed by means of their ends. The bolts pass through corresponding holes in the flange of a cover, which is mounted on the vessel. Securing nuts are screwed onto threads on the projecting parts of the bolts so that the desired connection of the parts is made. In these and similar connections there is frequently the necessity, when screwing the bolts into their receiving threads or when screwing them out, for the screwing procedures to be carried out by suitable apparatus with as little use of manual work as possible. This applies in particular for large and heavy screw bolts and for those screw connections which are in danger regions, such as for example in nuclear reactors. In order to prevent damage to the thread when screwing out or in, it is furthermore desirable or necessary, during rotating, to apply an axial pulling force, which if possible can support the full weight of the bolt so that the thread is accordingly relieved.
In order to achieve this there must be a coupling system which is capable of transmitting a torque delivered by a drive and a pulling force delivered by a further device to the bolt. In this respect there is usually also the requirement that the coupling system can be completely detached from the bolt and can also be reconnected thereto according to the circumstances.
Previously, for such purposes, various elements engaging at a number of outer places on the bolt were used. For this the bolt had to have corresponding profiled sections for locking parts, for attaching keys etc.